1. Field of the Invention
The present invention refers to a method for radioactive marking of an oncofetal urine peptide and the use of the peptide as a cancer diagnostics, preferably in gynecological cancer.
2. Prior Art
The diagnostics of cancer patients is difficult as the disease does not usually give any symptoms in its initial state. In many cases the disease is discovered only in a state when the cancer tumour is so big that the disease is incurable or difficult to cure. In this state the tumour also often has sent out metastases. If the disease is discovered in an early state it is however often possible to cure it completely. For this reason one has been looking for tumour markers, i.e. substances produced by the tumour or being generated as a result of the tumour disease which could be used for diagnostics of the disease. Tumour markers of this kind are for instance alphafetoprotein (AFP) and carcinoembryonal antigen (CEA). For a closer description of CEA is referred for instance to the U.S. Pat. No. 3,663,684 (Freedman, S.O.). AFP and CEA can be detected in serum samples and increased concentrations indicate certain tumour diseases. AFP is a relatively sensitive marker for liver and testis cancer, but is not useful in other tumours. CEA is increased in a number of tumour disease but the specificity of the determination is relatively low. Therefore, CEA-determinations are mainly used for monitoring patients with increased values. For choricarcinon there is a very specific marker, koriongonadotropin (hCG) which is also produced in normal placenta. By determining the hCG recurrences can be diagnosed in a very early state. Because of this, the treatment of choriocarcinon is nowadays very successful.
Good tumour markers thus have a very high value but for most tumours no markers exist or exist only in a certain percentage or alternatively in a very late state of the disease.